Pagination does not behave as I expect

[eluser]Unknown[/eluser]
I am trying out CodeIgniter and my first experiment is just a Guestbook, but the Pagination Library does some strange things. My code is this:

Code:

function page($number=1)
    {
        $this->load->helper(array('form','url'));
        $this->load->model('guestbookentries','entries');
        
        $this->load->library('pagination');
        $config['base_url'] = site_url("guestbook/page");
        $config['total_rows'] = $this->entries->count();
        $per_page = 3;
        $config['per_page'] = $per_page;
        $this->pagination->initialize($config);
        
        $data['title'] = "Gästebuch";
        $data['entries'] = $this->entries->get_some_after($per_page,$number);
        $data['pagination'] = $this->pagination->create_links();
        
        $this->load->view('guestbook', $data);
    }

get_some_after is SELECT LIMIT OFFSET.
I would have expected, that I should have written

Code:

$data['entries'] = $this->entries->get_some_after($per_page,$per_page*$number-$per_page);

but I get links in my Pagination like .../page, .../page/3, .../page/6 etc.
I'd rather have /1, /2, /3 etc.

Is there something wrong with my code, or is this the way it is meant to be?